In the related art, the face image of the driver is captured by a camera which is fixed to a steering column of the vehicle, the position of the black eye of the driver is detected from the captured image, and the line of sight of the driver is detected, in order to avoid the crash of the vehicle.
However, a red-eye phenomenon occurs, for example, at night where the amount of light outside the vehicle is small. Therefore, it is necessary to detect the red eye of the driver from image information in order to detect the line of sight of the driver at night where the amount of light outside the vehicle is small.
However, in general, it is more difficult to detect the red eye than to detect the black eye. Patent Literature 1 discloses a technique which sequentially scans an image from the region in which a red-eye region is likely to be present to detect the red eye of the driver.